In a support plate structure of the above kind, the support bearing carries, for rotation in it, the drive spindle of the screen wiper mechanism, the drive spindle having a wiper arm secured to it, above the bearing, for the usual back and forth movement in contact with the surface to be wiped. The drive spindle is coupled, through a suitable linkage which imparts the necessary oscillating motion to it, to driving means which are fixed on the support plate of the assembly.
In one known design of such a structure, the elongate structural element is a tubular member, and its free end portion secures the tubular member and the bearing together in such a way as to secure the bearing against any displacement in rotation about the tubular member and against any displacement in the direction of the axis defined by the latter.
In the known design described and shown in German published patent specification No. DE 2 920 899A, the bearing comprises a cylindrical portion in the form of a stump or pedestal, which is received in the open free end portion of the tubular structural element. The bearing has at least one longitudinal opening which is substantially parallel to the axis of this pedestal, and a portion of the wall in facing relationship with the tubular structural element is forced into this opening, by deformation using a seaming punch, in a direction which is substantially parallel to the axis of the tubular element. This technique secures the end portion of the tubular structural element by seaming on to the cylindrical bearing portion that consists of the pedestal, with the latter being inside the free end of the tubular element.
However, it has been found that such an arrangement does not afford a connection that is rigid enough to prevent relative displacement, both in rotation and in straight line motion, between the bearing and the tubular structural element. Thus, in use, an axial clearance is found to occur in the joint.
In addition, such a technique does not readily permit sufficiently accurate axial and angular positioning of the support bearing with respect to the tubular structural element during the seaming operation. Moreover, it calls for the use of a support bearing the body of which is made of metal: as a result, this bearing is very heavy.